Patent application number | Description | Published |
20090037079 | Air-fuel ratio control apparatus and method for an internal combustion engine - When an internal combustion engine including a plurality of cylinders is operating steadily, an index value relating to an actual hydrogen content in exhaust gas downstream of a portion where exhaust passages from the cylinders merge, and upstream of a catalyst is detected. When an index value relating to the actual hydrogen content in the exhaust gas is larger than a determination index value relating to a hydrogen content corresponding to a permissible limit of air-fuel ratio variation, it is determined that there is abnormal air-fuel ratio variation between the cylinders. | 02-05-2009 |
20090145109 | Catalyst degradation diagnosis device and diagnosis method for internal combustion engine - The oxygen storage capacity preceding a previous oxygen storage capacity and the previous oxygen storage capacity of each of an upstream catalyst and a downstream catalyst are measured, and a present oxygen storage capacity of the downstream catalyst is measured. Then, sulfur poisoning of the upstream catalyst and the downstream catalyst is detected on the basis of an oxygen storage capacity change amount of each of the upstream catalyst and the downstream catalyst from the oxygen storage capacity preceding the previous one to the previous oxygen storage capacity, and the oxygen storage capacity change amount of the downstream catalyst from the previous oxygen storage capacity to the present oxygen storage capacity. The presence/absence of the sulfur poisoning can be accurately detected by utilizing the difference between the manners of sulfur poisoning of the two catalysts. | 06-11-2009 |
20090211350 | APPARATUS AND METHOD FOR DETECTING ABNORMALITY OF INTER-CYLINDER AIR-FUEL RATIO DISPERSION IN MULTI-CYLINDER INTERNAL COMBUSTION ENGINE - An apparatus or a method for detecting an abnormality of inter-cylinder air-fuel ratio dispersion in a multi-cylinder internal combustion engine according to the invention is equipped with a catalytic element that purifies exhaust gas of hydrogen, a first air-fuel ratio sensor that detects an air-fuel ratio of exhaust gas that has not passed through the catalytic element, a second air-fuel ratio sensor that detects an air-fuel ratio of exhaust gas that has passed through the catalytic element, a device that detects an abnormality of inter-cylinder air-fuel ratio dispersion on the basis of a divergence state of a detected value of a second air-fuel ratio to a lean side from a detected value of a first air-fuel ratio, and a device that forcibly reduces fuel injection amounts in cylinders individually when an abnormality on dispersion is detected by the abnormality detector, detects a divergence state of the detected value of the second air-fuel ratio to the lean side from the detected value of the first air-fuel ratio at this time, and specifies as an abnormal cylinder that one of the cylinders in which a value indicating this divergence state has become smaller than at a time of detection of the abnormality of dispersion. | 08-27-2009 |
20090260347 | APPARATUS AND METHOD FOR DETECTING ABNORMAL AIR-FUEL RATIO VARIATION AMONG CYLINDERS OF MULTI-CYLINDER INTERNAL COMBUSTION ENGINE - An apparatus and a method for detecting abnormal air-fuel ratio variation among cylinders of a multi-cylinder internal combustion engine are provided. The apparatus includes: a catalyst that is provided in an exhaust passage of the multi-cylinder internal combustion engine; a catalyst temperature detection unit that detects a temperature of the catalyst; a catalyst temperature estimation unit that estimates a temperature of the catalyst based on an engine operating state; and an abnormality detection unit that determines whether abnormal air-fuel ratio variation among the cylinders has occurred based on the detected temperature of the catalyst and the estimated temperature of the catalyst. | 10-22-2009 |
20100083637 | DEGRADATION DIAGNOSTIC APPARATUS FOR NOX CATALYST - A NOx amount capable of being absorbed by a criteria catalyst as a boundary between degradation and normality is supplied to a NOx storage reduction catalyst and thereafter, a reducer amount corresponding to the NOx amount is supplied by a rich spike operation. Degradation of the NOx catalyst is determined based upon the output of the NOx sensor at this time. Since the degradation of the NOx catalyst is determined only by a magnitude of the NOx sensor output, the degradation diagnosis can be performed with high precision. While the catalyst is normal, the excessive reducers are not supplied and therefore, deterioration of the fuel consumption can be prevented. | 04-08-2010 |
20100211290 | ABNORMALITY DIAGNOSTIC DEVICE AND ABNORMALITY DIAGNOSTIC METHOD FOR MULTICYLINDER INTERNAL COMBUSTION ENGINE - A fuel injection amount from fuel injection valves is actively controlled and an input air-fuel ratio is caused forcibly to oscillate. A system from the fuel injection valves to the air-fuel ratio sensor is simulated by a first order delay system, and a gain and time constant are identified on the basis of the input air-fuel ratio relating to the model and an output air-fuel ratio obtained from the air-fuel ratio sensor. The presence of an air-fuel ratio abnormal variation is diagnosed on the basis of whether or not the identified values of the gain and the time constant are less than a first and second predetermined values respectively. | 08-19-2010 |
20100257922 | ABNORMALITY DIAGNOSIS APPARATUS AND ABNORMALITY DIAGNOSIS METHOD FOR NOx CATALYST - An abnormality diagnosis apparatus for an NOx catalyst of the present invention measures an index value (R) regarding an NOx clarification capacity of an NOx catalyst and determines an abnormality of the NOx catalyst based on index values (R | 10-14-2010 |
20100307135 | APPARATUS AND METHOD FOR DIAGNOSING CATALYST DETERIORATION - A catalyst deterioration diagnosing apparatus is provided with means for performing stoichiometric feedback control on the air-fuel ratio based on at least output from an upstream air-fuel ratio sensor provided upstream of a catalyst, means for measuring the oxygen storage capacity of the catalyst, and means for correcting the measured value of the oxygen storage capacity based on at least the output behavior of a downstream air-fuel ratio sensor provided downstream of the catalyst during the stoichiometric feedback control. The measured value of the oxygen storage capacity is corrected using the output behavior of the downstream air-fuel ratio sensor during stoichiometric feedback control. The diagnostic is performed after eliminating the effects from sulfur by correcting the measured value to a value corresponding to when low sulfur fuel is used, which makes it possible to prevent an erroneous diagnosis from being made. | 12-09-2010 |
20110282541 | MONITORING APPARATUS FOR A MULTI-CYLINDER INTERNAL COMBUSTION ENGINE - A monitoring apparatus including a catalytic converter, an upstream air-fuel ratio sensor, and a downstream air-fuel ratio sensor; calculates a sub feedback amount to have an air-fuel ratio represented based on an output value of the downstream air-fuel ratio sensor coincide with a stoichiometric air-fuel ratio; and controls an fuel injection amount based on an output value of the upstream air-fuel ratio sensor and the sub feedback amount, in such a manner that an air-fuel ratio of a mixture supplied to an engine coincides with the stoichiometric air-fuel ratio. | 11-17-2011 |
20110283981 | APPARATUS FOR ACQUIRING RESPONSIBILITY OF OXYGEN CONCENTRATION SENSOR - The fact that “with respect to a process in which the output value of a downstream air-fuel ratio sensor (sensor output value) is inverted from the minimum output value to the maximum output value during execution of an active control, the local maximum and minimum values of the secondary differential value of the sensor output value is widely affected by the size of the response delay of the downstream air-fuel ratio sensor and the size of the degree of the degradation of the three-way catalyst” is utilized. By preliminarily acquiring and memorizing, as maps, these relations obtained through an experiment, and applying the “local maximum and minimum values of the secondary differential value of the sensor output value” calculated from the transition of the sensor output value acquired during execution of the active control to the maps, the response delay (time constant) of the downstream air-fuel ratio sensor is acquired. | 11-24-2011 |
20110288739 | APPARATUS FOR DETERMINING AN AIR-FUEL RATIO IMBALANCE AMONG CYLINDERS OF AN INTERNAL COMBUSTION ENGINE - An apparatus for determining an air-fuel ratio imbalance among cylinders including an upstream air-fuel ratio sensor, a catalytic converter, and a downstream air-fuel ratio sensor disposed at positions downstream of an exhaust gas aggregated portion, calculates a sub feedback amount to have an output value of the downstream air-fuel ratio sensor coincides with a value corresponding to the stoichiometric air-fuel ratio, and performs an air-fuel ratio feedback control to have an air-fuel ratio of a mixture supplied to an engine based on the sub feedback amount and the output value of the upstream air-fuel ratio sensor. | 11-24-2011 |
20110290217 | ENGINE SYSTEM CONTROL DEVICE - The present invention provides an engine system control device to be applied to an engine system provided with an engine having a variable compression ratio mechanism capable of changing a compression ratio. In the case where generation of failure in a compression ratio control system is detected, determination of a state of a member placed in an intake and exhaust system of the engine is inhibited. | 12-01-2011 |
20120035831 | AIR-FUEL RATIO IMBALANCE AMONG CYLINDERS DETERMINING APPARATUS FOR A MULTI-CYLINDER INTERNAL COMBUSTION ENGINE - A judging device comprises a catalyst, an upstream air/fuel ratio sensor having an air/fuel ratio sensing element covered with a diffusion resistance layer, and a downstream air/fuel ratio sensor. The judging device performs main feedback control to equalize the air/fuel ratio indicated by the output value of the upstream air/fuel ratio sensor to an upstream target air/fuel ratio and sub-feedback control to equalize the output value of the downstream air/fuel ratio sensor to a downstream target value. The judging device acquires “an imbalance judging parameter” which increases with “the increase of the difference between the amount of hydrogen contained in the exhaust gas before the exhaust gas passes through the catalyst and that after the exhaust gas passes through the catalyst” according to the sub-feedback amount. When the imbalance judging parameter is larger than an abnormality judgment threshold, the judging device judges that an air/fuel ratio imbalance among the cylinders has occurred. The judging device does not make judgment on air/fuel ratio imbalance among the cylinders if a predetermined judgment prohibition condition is satisfied, for example, if the flow of the exhaust gas is a predetermined value or more. | 02-09-2012 |
20120095664 | MALFUNCTION DETECTION APPARATUS AND MALFUNCTION DETECTION METHOD FOR AN EGR SYSTEM - A determination is made more simply as to a malfunction of a low pressure EGR device that supplies an EGR gas from a low pressure EGR passage connecting between an exhaust passage at a location downstream of a turbine and an intake passage. Provision is made for a high pressure EGR device that connects between the exhaust passage at a location upstream of the turbine and the intake passage, the low pressure EGR device that connects between the exhaust passage at a location downstream of the turbine and the intake passage, and a detection unit that detects a malfunction of the low pressure EGR device from the degree of opening of a high pressure EGR valve at the time when the EGR gas is supplied from both the high pressure EGR device and the low pressure EGR device, and at the time when the high pressure EGR valve of the high pressure EGR device is controlled in a feedback manner so as to direct an amount of EGR gas in a cylinder toward a target range of the amount of EGR gas, while carrying out open loop control of a low pressure EGR valve of the low pressure EGR device. | 04-19-2012 |
20120116651 | INTER-CYLINDER AIR-FUEL RATIO IMBALANCE JUDGMENT DEVICE FOR MULTI-CYLINDER INTERNAL COMBUSTION ENGINE - When the intake air amount is smaller than the specific intake air amount, the unit air-fuel ratio change amount calculated during the engine operation is corrected such that the unit air-fuel ratio change amount increases in the condition that the base unit air-fuel ratio change amount is an upper limit and when the intake air amount is greater than the specific intake air amount, the unit air-fuel ratio change amount calculated during the engine operation is corrected such that the unit air-fuel ratio change amount decreases in the condition that the base unit air-fuel ratio change amount is a lower limit. When the corrected unit air-fuel ratio change amount is greater than the judgment value, it is judged that the inter-cylinder air-fuel ratio imbalance condition occurs. | 05-10-2012 |
20120160022 | APPARATUS FOR DETERMINING AN AIR-FUEL RATIO IMBALANCE AMONG CYLINDERS OF AN INTERNAL COMBUSTION ENGINE - An air-fuel ratio imbalance among cylinders determining apparatus according to the present invention is applied to a multi-cylinder internal combustion engine in which a compression ratio is variable. The determining apparatus obtains, using at least an output value of an upstream air-fuel ratio sensor disposed for a catalyst, an “imbalance determining parameter” which becomes larger as a degree of an imbalance among “individual cylinder air-fuel ratios” becomes larger, each of the individual cylinder air-fuel ratios being an air-fuel ratio of a mixture supplied to each of cylinders. Further, the determining apparatus determines that an air-fuel ratio imbalance state among cylinders is occurring, when the imbalance determining parameter is larger than a predetermined threshold. The determining apparatus changes the predetermined threshold in accordance with a mechanical compression ratio of the engine. | 06-28-2012 |
20120173116 | AIR-FUEL RATIO IMBALANCE DETERMINING APPARATUS AMONG CYLINDERS FOR AN INTERNAL COMBUSTION ENGINE - An air-fuel ratio imbalance among cylinders determining apparatus according to the present invention obtains an output Vabyfs of an air-fuel ratio sensor disposed at a portion downstream of an exhaust gas aggregated portion of an exhaust gas passage, and obtains a second-order differential value d2AF (a change rate of a change rate of a detected air-fuel ratio abyfs) of a detected air-fuel ratio abyfs represented by the air-fuel ratio sensor output Vabyfs. The imbalance determining apparatus determines that an air-fuel ratio imbalance state among cylinders is occurring when a detected air-fuel ratio second-order differential corresponding value (for example, a second-order differential value d2AF per se) obtained in accordance with the second-order differential value d2AF is larger than a first threshold value. | 07-05-2012 |
20130014641 | FAILURE DETECTION APPARATUS AND FAILURE DETECTION METHOD FOR A PARTICULATE FILTERAANM Takaoka; KazuyaAACI Susono-shiAACO JPAAGP Takaoka; Kazuya Susono-shi JPAANM Shibata; DaisukeAACI Numazu-shiAACO JPAAGP Shibata; Daisuke Numazu-shi JPAANM Sawada; HiroshiAACI Gotenba-shiAACO JPAAGP Sawada; Hiroshi Gotenba-shi JPAANM Kidokoro; ToruAACI Hadano-shiAACO JPAAGP Kidokoro; Toru Hadano-shi JP - The present invention is intended to detect a failure of a PM filter with a higher degree of accuracy. The present invention is provided with: a PM trapping efficiency calculation part to calculate a PM trapping efficiency (which is a proportion of an amount of particulate matter trapped with respect to an amount of inflow particulate matter) based on an amount of inflow particulate matter obtained by an inflow particulate matter obtaining part, and an amount of outflow particulate matter detected by a PM sensor; and a failure detection part to make a determination that a failure has occurred in the PM filter, in cases where there has appeared a tendency for the PM trapping efficiency to decrease during a period of time until the execution of the following filter regeneration processing is started after the completion of execution of the filter regeneration processing. | 01-17-2013 |
20130098146 | CATALYST DETERIORATION DETECTION APPARATUS AND CATALYST DETERIORATION DETECTION METHOD FOR INTERNAL COMBUSTION ENGINE - Provision is made for a catalyst that is arranged in an exhaust passage of an internal combustion engine and has an oxidation function, downstream side temperature detection means that detects the temperature of an exhaust gas at a downstream side from the catalyst, and addition means that adds a reducing agent into the exhaust gas from an upstream side from the catalyst, wherein there are also provided correlation value calculation means that calculates a correlation value which is correlated with an amount of change of the temperature detected by the downstream side temperature detection means when the reducing agent is added by the addition means and when a transient operation of the internal combustion engine is carried out, and determination means that determines a deterioration of the catalyst by making a comparison between the correlation value and a threshold value which indicates the deterioration of the catalyst. | 04-25-2013 |
20130139795 | FAILURE DIAGNOSIS APPARATUS OF EGR SYSTEM - In the engine including an MPL-EGR system having an HPL-EGR mechanism | 06-06-2013 |
20130152552 | EXHAUST EMISSION CONTROL DEVICE OF INTERNAL COMBUSTION ENGINE - An exhaust emission control device of an internal combustion engine capable of effectively restoring an NSR catalyst from sulfur poisoning while suppressing reduction of fuel efficiency and worsening of emission, in the internal combustion engine including the NSR catalyst and SCR. An exhaust emission control device of an internal combustion engine capable of a lean burn operation includes a TWC that is placed in an exhaust passage of the internal combustion engine and supports a precious metal in an inside thereof, an NSR catalyst that is placed at an exhaust downstream side of the TWC and supports a precious metal and a base in an inside thereof, and an SCR that is placed in the exhaust passage at a downstream side of the NSR catalyst, wherein the NSR catalyst is placed in a region in which a bed temperature at a time of an operation thereof becomes 500° C. to 750° C. The TWC and the NSR catalyst are preferably configured as an SC of a tandem structure in which the TWC and the NSR catalyst are integrated by being serially arranged. | 06-20-2013 |
20130173140 | CONTROL APPARATUS AND METHOD FOR AN INTERNAL COMBUSTION ENGINE - The present invention is intended to provide a technique of improving exhaust emissions at the time of starting up of an internal combustion engine, without decreasing the performance of a catalyst at the time of the engine starting up. The present invention is provided with the catalyst that is arranged in an exhaust passage of the internal combustion engine in which a plurality of kinds of fuels are able to be used, and serves to adsorb and remove exhaust gas components discharged from the internal combustion engine, wherein in cases where among the plurality of kinds of fuels, a first fuel is used in which unburnt fuel components thereof are easily adsorbed to the catalyst, at the time when a request is made for stopping the internal combustion engine, said first fuel is changed to a second fuel thereby to operate said internal combustion engine until said internal combustion engine is stopped. | 07-04-2013 |
20130192208 | FILTER FAILURE DETECTION APPARATUS OF AN INTERNAL COMBUSTION ENGINE - A failure of a filter is detected with a higher degree of accuracy. There are provided a filter that is arranged on an exhaust passage of an internal combustion engine for collecting a substance contained in an exhaust gas, a substance amount detection part that is arranged on the exhaust passage at a downstream side of the filter for detecting an amount of substance in the exhaust gas, a flow speed detection part that detects or estimates a flow speed of the exhaust gas which passes through the filter, and a determination part that makes a determination that the filter is in a failure, when the higher the flow speed of the exhaust gas passing through the filter, the larger a ratio of an amount of change in the amount of substance to an amount of change in the flow speed of the exhaust gas becomes. | 08-01-2013 |
20130199163 | FUEL INJECTION SYSTEM OF AN INTERNAL COMBUSTION ENGINE - In a fuel injection system of an internal combustion engine in which a first fuel, which has a property to inhibit the adsorption of exhaust gas components by an exhaust gas purification catalyst, and the second fuel, which has a property not to inhibit the adsorption of the exhaust gas components by the exhaust gas purification catalyst, are able to be selectively used, the present invention has a task to decrease an amount of consumption of the second fuel in a suitable manner. In order to solve this task, the fuel injection system of an internal combustion engine according the present invention is constructed such that the second fuel is first supplied to the internal combustion engine when the exhaust gas purification catalyst is in a cold state, and a change from the second fuel to the first fuel is then made before the exhaust gas purification catalyst subsequently rises in temperature to an activation temperature thereof. | 08-08-2013 |
20130216436 | CATALYST DETERIORATION JUDGING SYSTEM - The deterioration judgment for an absorption reduction type NOx catalyst is performed quickly and correctly. A catalyst deterioration judging system includes a supply unit which supplies a reducing agent, a measuring unit which measures a NOx concentration in an exhaust gas at a position downstream from the catalyst, a control unit which regulates an amount of the reducing agent so that an air-fuel ratio of the exhaust gas is a lean air-fuel ratio when the reducing agent is supplied from the supply unit, and a judging unit which judges deterioration of the catalyst on the basis of the NOx concentration measured by the measuring unit when the amount of the reducing agent is regulated so that the air-fuel ratio of the exhaust gas is the lean air-fuel ratio when NOx is absorbed by the catalyst. | 08-22-2013 |
20130261934 | APPARATUS FOR DETERMINING AN AIR-FUEL RATIO IMBALANCE AMONG CYLINDERS OF AN INTERNAL COMBUSTION ENGINE - An apparatus for determining an air-fuel ratio imbalance among cylinders based on an output value of an air-fuel ratio sensor, an imbalance determination parameter which becomes larger or smaller as a difference among air-fuel ratios becomes larger, and performs determining an air-fuel ratio imbalance among cylinders based on a result of a comparison between the imbalance determination parameter and a imbalance determination threshold. The determining apparatus calculates a purge correction coefficient which compensates for a change in the air-fuel ratio due to an evaporated fuel gas which is generated in a fuel tank, while the evaporated fuel gas is being introduced into an intake passage, and corrects a fuel injection amount with the purge correction coefficient FPG. | 10-03-2013 |
20130330234 | CATALYST DETERIORATION JUDGING SYSTEM - The deterioration judgment for an absorption reduction type NOx catalyst is performed quickly and correctly. A catalyst deterioration judging system includes a judging unit which judges that the absorption reduction type NOx catalyst is deteriorated if a detected value of an NH | 12-12-2013 |
20130336841 | CATALYST DETERIORATION DETERMINATION SYSTEM - The determination of deterioration of a NOx storage reduction catalyst ( | 12-19-2013 |
20140003999 | CATALYST DETERIORATION DETERMINATION SYSTEM | 01-02-2014 |
20140023561 | EXHAUST CLEANER FOR INTERNAL COMBUSTION ENGINE - The exhaust cleaner for internal combustion engine is equipped with NOx storage reduction catalyst ( | 01-23-2014 |
20140033687 | FUEL INJECTION CONTROL SYSTEM OF AN INTERNAL COMBUSTION ENGINE - The present invention has its object to provide a technique which can eliminate HC poisoning of an exhaust gas purification catalyst in a suitable manner in a fuel injection control system of an internal combustion engine which can use a liquid fuel and a gas fuel. In order to achieve this object, the present invention is constructed such that in the fuel injection control system of an internal combustion engine capable of using a liquid fuel and a gas fuel, when HC poisoning of the exhaust gas purification catalyst has occurred, HC poisoning is intended to be eliminated by causing the internal combustion engine to operate by the use of the gas fuel if the temperature of the exhaust gas purification catalyst is less than a specified value, whereas the elimination of HC poisoning is intended by causing the internal combustion engine to operate by the use of the liquid fuel if the temperature of an exhaust gas purification device is not less than the specified value. | 02-06-2014 |
20140186220 | EXHAUST GAS PURIFICATION APPARATUS FOR AN INTERNAL COMBUSTION ENGINE - In cases where an NOx selective reduction catalyst is provided at a location downstream of an NOx storage reduction catalyst, NOx purification performance in an exhaust gas purification apparatus as a whole is maintained, irrespective of deterioration of the NOx storage reduction catalyst. For this purpose, the reduction of NOx in the NOx storage reduction catalyst is promoted more when the degree of deterioration of the NOx storage reduction catalyst or the NOx selective reduction catalyst is low than when it is high, and the reduction of NOx in the NOx selective reduction catalyst is promoted more when the degree of deterioration of the NOx storage reduction catalyst or the NOx selective reduction catalyst is high than when it is low. | 07-03-2014 |
20140190150 | EXHAUST GAS PURIFICATION APPARATUS FOR AN INTERNAL COMBUSTION ENGINE - In cases where at the upstream side of an NOx selective reduction catalyst there is provided another catalyst, sulfur poisoning of both the catalysts is recovered in an appropriate manner. To this end, provision is made for an NH | 07-10-2014 |
20140199210 | EXHAUST GAS PURIFICATION APPARATUS FOR AN INTERNAL COMBUSTION ENGINE - A reduction in the accuracy of a failure determination of a filter due to a reduction in the detection accuracy of a PM sensor is suppressed. In order to achieve this, provision is made for a filter, an NOx selective reduction catalyst at the downstream side of the filter, a supply device for supplying a reducing agent to the NOx selective reduction catalyst, a PM sensor for detecting an amount of particulate matter in an exhaust gas at the downstream side of the NOx selective reduction catalyst, and a supply decrease part that makes an amount of supply of the reducing agent smaller in cases where at least one of the following conditions is satisfied than in cases where any of the conditions is not satisfied, wherein the conditions include: a condition in which the temperature of the NOx selective reduction catalyst is equal to or less than a threshold value; a condition in which the temperature of the exhaust gas is equal to or less than a threshold value; a condition in which the flow rate of the exhaust gas is equal to or larger than a threshold value; and a condition in which the amount of adsorption of the reducing agent in the NOx selective reduction catalyst is equal to or larger than a threshold value. | 07-17-2014 |
20140216020 | WARM-UP SYSTEM FOR EXHAUST SYSTEM OF INTERNAL COMBUSTION ENGINE - An object of the invention is to prevent a situation in which failure diagnosis for an exhaust system component in an internal combustion engine cannot be completed from continuing for an unduly long period of time. A warm-up system for an exhaust system of an internal combustion engine according to the invention includes a warm-up control performing unit that performs warm-up control for warming up an exhaust system component upon start-up of the internal combustion engine and a failure diagnosis performing unit that performs failure diagnosis for the exhaust system component after the completion of warm-up of the exhaust system component. If a situation in which the operation of the internal combustion engine is stopped after the start of operation of the internal combustion engine before the completion of the failure diagnosis for the exhaust system component performed by the failure diagnosis performing unit has been repeated for a predetermined period of time, the warm-up control performing unit changes the warm-up control performed upon start-up of the internal combustion engine after the predetermined period of time has elapsed to a control that can raise the temperature of the exhaust system component more quickly than the warm-up control performed during the aforementioned predetermined period. | 08-07-2014 |
20140234174 | EXHAUST GAS PURIFICATION APPARATUS FOR AN INTERNAL COMBUSTION ENGINE - A reduction in the accuracy of a failure determination of a filter due to a reduction in the detection accuracy of a PM sensor is suppressed. In order to achieve this, provision is made for a filter that is arranged in an exhaust passage of an internal combustion engine for trapping particulate matter contained in an exhaust gas, an NOx selective reduction catalyst that is arranged at the downstream side of the filter and reduces NOx by means of a reducing agent which is supplied thereto, a supply device that supplies the reducing agent to the NOx selective reduction catalyst from the upstream side of the NOx selective reduction catalyst, a PM sensor that detects an amount of the particulate matter in the exhaust gas at the downstream side of the NOx selective reduction catalyst, and a prohibition part that prohibits the use of a detected value of the PM sensor in cases where the reducing agent supplied from said supply device passes through the NOx selective reduction catalyst. | 08-21-2014 |